The TPS310x and TPS311x families of supervisory circuits provide circuit initialization and timing supervision, primarily for DSP and processor-based systems. During power-on, RESET is asserted low when the supply voltage (VDD) becomes higher than 0.4V. Thereafter, the supervisory circuit monitors VDD and keeps the RESET output low as long as VDD remains below the threshold voltage (VIT–). To provide proper system reset, after VDD surpasses the threshold voltage, an internal timer delays the transition of the RESET signal from low to high for the specified time. When VDD drops below VIT–, the output transitions low again. All the devices of this family have a fixed-sense threshold voltage (VIT–) set by an internal voltage divider. The TPS3103 and TPS3106 devices have an active-low, open-drain RESET output and either an integrated power-fail input (PFI) or SENSE input with corresponding outputs for monitoring other voltages. The TPS3110 has an active-low push/pull RESET and a watchdog timer to monitor the operation of microprocessors. All three devices have a manual reset pin that can be used to force the outputs low regardless of the sensed voltages. The product spectrum is designed for supply voltages of 0.9V up to 3.6V. The circuits are available in 6-pin SOT-23 packages. The TPS31xx family is characterized for operation over a temperature range of –40°C to 125°C.